Electrical heating element for utensils



Sept. 20, 1932. A, LARSEN 1,878,784

ELECTRICAL HEATING ELEMENT FOR UTENSILS Filed June 5, 1929 iamm g 1 .7.1? Larsen STATES ALANTSEB F. LARSEN, OF MANITOWOC, WISCONSIN, ASSIGNOR TO ALUMINUM GOODS MFG. CO., OF MANITOWOC, WISCONSIN ELECTRICAL HEATING ELEMENT FOR UTENSILS Application filed June 5,

This invention pertains to electric heating elements for various utensils, such as percolators, cookers, and the like, and has primarily for its object to provide such elements with simple, inexpensive, and reliable fusible means for breakin the electric heating circuit upon overheatlng of the utensil.

In connection with the foregoing, a more specific object resides in the provision of spring urged means for positively breaking a fusible link when the same becomes weaksued by the occurrence of a predetermined temperature, thus insuring arelatively quick action; and avoiding possibility of shorting the circuit, which frequently results where merely the complete fusing of the element is depended upon.

With the above and other objects in view, which will appear as the description proceeds, the invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the herein disclosed invention may be made as come within the scope of the claims.

In the accompanying drawing is illustrated one complete example of the physical em- 30 bodiment of the present invention constructed according to the best mode so far devised for the practical application of the principles thereof.

In the drawing, Figure 1 is a plan view of an element constructed in accordance with the present invention, parts being shown in section to more clearly illustrate structural features;

Figure 2 is an elevation with the element casing in section;

Figure. 3 is a detail of one of the arms carrying the fusible link;

Figure 4 is a detail of the other arm; and

Figure 5 is a. detail illustrating the manner of attaching the fusible link.

Referring now more particularly to the accompanying drawing in which the invention is shown as applied to a conventional type of electric heating element adapted to be used in connection with various cooking 1929. Serial No. 368,575.

utensils such as percolators, chafing dishes, cookers, and the like, the numeral 1 designat-es a refractory body, in which a resistance coil 2, indicated by dotted lines, is embedded in the usual manner. I

The refractory body 1 is covered by a metal casing 3 to protect the same against chipping andbreaking. The cover 4 of the casing 3 is provided with an offset flange 5 which carries the usual terminal prongs 6 that receive a socket member, not shown.

As best shown in Figure 1, one end of the resistance coil is connected to one of the terminal prongs 6 through the wire 7 while secured to the adjacent prong is an arm 8 having its outer end forked or slotted at 9 for receiving a fusible link 10.

Secured to the arm 8 by means of the bolt 11, and insulated therefrom, is an additional arm 12 slotted at 13 to correspond with the slotted end of the arm 8. Preferably, either one or both of the arms 8 and 12 are formed of resilient material normally urged apart in operative position and held under tension by the fusible link 10, the reduced portion of which engages in the forked ends of the arms, while the enlarged end portions 14 engage the arms and retain them in operative position. The link 10 is formed of any wellknown fusible alloy which will fuse or become weakened at a predetermined temperature.

' Thus, in operation, should the vessel, to which the element is attached, become heated past a predetermined degree, the link 10 will become weakened, whereupon the tension'between the forked ends of the arms 8 and 12 will cause the linkto be severed or broken,

which will break the resistance circuit, in

preventing rotary movement of the arm 8 on the terminal prong 6.

From the foregoing description, taken in connection with the drawing, it will be seen that a very simple, inexpensive, and reliable structure-has been provided, which will posi- 5 tively break the heating circuit upon the occurrence of a predetermined temperature adjacent the fusible link, it being understood that the link is affected only by the presence of excessive temperature, and not by the 70 amount of curren a.

In practice, the resistance circuits of heating elements of this kind are protected against excessive current through conventional fuses provided in the supply circuit. However, damage and fire hazard often re- 7 sults through overheating of the utensil to which the unit is attached, especially where the contents of the utensil have been consumed.,

The presentinvention is designed to effectively overcome this objection. While the arms 8 and 12, which carry the fusible link 10, have been described as formed of resilient material, it will also be understood that any means might be employed for creating tension between the arms to normally urge them apart, the onlyrequirement residing in the necessity for creating a tension between the armsto cause breakage of the fusible link, as the same becomes weakened, prior to complete fusing. Such action insures a quick breaking of the heating circuit and avoids possibility of shortening the various connections, which frequently occurs Where the fusible element is fused to such an extent that the same can run. 8

It will also be seen that the manner of connecting the fusible link to the arms 10 and 12, does away with fastening devices and permits ready renewal of the link should replacement be required. Y

I claim:

In an electrical heating element, a fusible switch comprising a resilient current conducting arm, a bolt carried by said arm and insulated therefrom, a second arm carried by the bolt and spaced from the first arm, said arms being provided with slots adjacent corresponding ends, means normally urging the slotted ends of said arms apart, a fusible link engaged in the slotted ends to connect said arms, and enlarged ends on'said fusible link engaging the outer faces of the arms normally restraining said arms againstthe tension exerted thereon.

In testimony that I claim the foregoing I have hereunto set my hand at Manitowoc, in the county of Manitowoc and State of Wisconsin. I r

, ALANTSER F. LARSEN. 

